Control knob



FIG. 1 is a top plan view of a control knob;

FIG. 2 is a bottom plan view of the control knob of FIG. 1;

FIG. 3 is a right side elevational view of the control knob of FIG. 1;

FIG. 4 is a rear elevational view of the control knob of FIG. 1;

FIG. 5 is a front elevational view of the control knob of FIG. 1;

FIG. 6 is a left side elevational view of the control knob of FIG. 1;

FIG. 7 is a top-right rear isometric view of the control knob of FIG. 1;

FIG. 8 is a top-right front isometric view of the control knob of FIG. 1; and,

FIG. 9 is a top-left front isometric view of the control knob of FIG. 1.

The broken lines and unshaded areas shown in the figures are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a control knob, as shown and described. 